NFSD: fix regression with setting ACLs.

A recent patch moved ACL setting into nfsd_setattr().
Unfortunately it didn't work as nfsd_setattr() aborts early if
iap->ia_valid is 0.

Remove this test, and instead avoid calling notify_change() when
ia_valid is 0.

This means that nfsd_setattr() will now *always* lock the inode.
Previously it didn't if only a ATTR_MODE change was requested on a
symlink (see Commit 15b7a1b86d66 ("[PATCH] knfsd: fix setattr-on-symlink
error return")). I don't think this change really matters.

Fixes: c0cbe70742f4 ("NFSD: add posix ACLs to struct nfsd_attrs")
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 9f486b788ed09fdd007ca342bc4f4e9fe34273cb..19f28c33e44d19f53b55e500a2c721246095bb7f 100644 (file)
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -300,6 +300,10 @@ commit_metadata(struct svc_fh *fhp)
 static void
 nfsd_sanitize_attrs(struct inode *inode, struct iattr *iap)
 {
+       /* Ignore mode updates on symlinks */
+       if (S_ISLNK(inode->i_mode))
+               iap->ia_valid &= ~ATTR_MODE;
+
        /* sanitize the mode change */
        if (iap->ia_valid & ATTR_MODE) {
                iap->ia_mode &= S_IALLUGO;
@@ -353,7 +357,7 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp,
        int             accmode = NFSD_MAY_SATTR;
        umode_t         ftype = 0;
        __be32          err;
-       int             host_err;
+       int             host_err = 0;
        bool            get_write_count;
        bool            size_change = (iap->ia_valid & ATTR_SIZE);
 
@@ -391,13 +395,6 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp,
        dentry = fhp->fh_dentry;
        inode = d_inode(dentry);
 
-       /* Ignore any mode updates on symlinks */
-       if (S_ISLNK(inode->i_mode))
-               iap->ia_valid &= ~ATTR_MODE;
-
-       if (!iap->ia_valid)
-               return 0;
-
        nfsd_sanitize_attrs(inode, iap);
 
        if (check_guard && guardtime != inode->i_ctime.tv_sec)
@@ -448,8 +445,10 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp,
                        goto out_unlock;
        }
 
-       iap->ia_valid |= ATTR_CTIME;
-       host_err = notify_change(&init_user_ns, dentry, iap, NULL);
+       if (iap->ia_valid) {
+               iap->ia_valid |= ATTR_CTIME;
+               host_err = notify_change(&init_user_ns, dentry, iap, NULL);
+       }
 
 out_unlock:
        if (attr->na_seclabel && attr->na_seclabel->len)